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linux/arch/s390/pci/pci_bus.c

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s390/pci: create zPCI bus The zPCI bus is in charge to handle common zPCI resources for zPCI devices. Creating the zPCI bus, the PCI bus, the zPCI devices and the PCI devices and hotplug slots done in a specific order: - PCI hotplug slot creation needs a PCI bus - PCI bus needs a PCI domain which is reported by the pci_domain_nr() when setting up the host bridge - PCI domain is set from the zPCI with devfn 0 this is necessary to have a reproducible enumeration Therefore we can not create devices or hotplug slots for any PCI device associated with a zPCI device before having discovered the function zero of the bus. The discovery and initialization of devices can be done at several points in the code: - On Events, serialized in a thread context - On initialization, in the kernel init thread context - When powering on the hotplug slot, in a user thread context The removal of devices and their parent bus may also be done on events or for devices when powering down the slot. To guarantee the existence of the bus and devices until they are no more needed we use kref in zPCI bus and introduce a reference count in the zPCI devices. In this patch the zPCI bus still only accept a device with a devfn 0. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 12:45:43 +03:00
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright IBM Corp. 2020
*
* Author(s):
* Pierre Morel <pmorel@linux.ibm.com>
*
*/
#define KMSG_COMPONENT "zpci"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/delay.h>
#include <linux/seq_file.h>
#include <linux/jump_label.h>
#include <linux/pci.h>
#include <linux/printk.h>
#include <asm/pci_clp.h>
#include <asm/pci_dma.h>
#include "pci_bus.h"
static LIST_HEAD(zbus_list);
static DEFINE_SPINLOCK(zbus_list_lock);
static int zpci_nb_devices;
/* zpci_bus_scan
* @zbus: the zbus holding the zdevices
* @ops: the pci operations
*
* The domain number must be set before pci_scan_root_bus is called.
* This function can be called once the domain is known, hence
* when the function_0 is dicovered.
*/
static int zpci_bus_scan(struct zpci_bus *zbus, int domain, struct pci_ops *ops)
{
struct pci_bus *bus;
int rc;
rc = zpci_alloc_domain(domain);
if (rc < 0)
return rc;
zbus->domain_nr = rc;
bus = pci_scan_root_bus(NULL, ZPCI_BUS_NR, ops, zbus, &zbus->resources);
if (!bus) {
zpci_free_domain(zbus->domain_nr);
return -EFAULT;
}
zbus->bus = bus;
pci_bus_add_devices(bus);
return 0;
}
static void zpci_bus_release(struct kref *kref)
{
struct zpci_bus *zbus = container_of(kref, struct zpci_bus, kref);
s390/pci: Handling multifunctions We allow multiple functions on a single bus. We suppress the ZPCI_DEVFN definition and replace its occurences with zpci->devfn. We verify the number of device during the registration. There can never be more domains in use than existing devices, so we do not need to verify the count of domain after having verified the count of devices. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-22 16:15:23 +03:00
if (zbus->bus) {
pci_lock_rescan_remove();
pci_stop_root_bus(zbus->bus);
s390/pci: create zPCI bus The zPCI bus is in charge to handle common zPCI resources for zPCI devices. Creating the zPCI bus, the PCI bus, the zPCI devices and the PCI devices and hotplug slots done in a specific order: - PCI hotplug slot creation needs a PCI bus - PCI bus needs a PCI domain which is reported by the pci_domain_nr() when setting up the host bridge - PCI domain is set from the zPCI with devfn 0 this is necessary to have a reproducible enumeration Therefore we can not create devices or hotplug slots for any PCI device associated with a zPCI device before having discovered the function zero of the bus. The discovery and initialization of devices can be done at several points in the code: - On Events, serialized in a thread context - On initialization, in the kernel init thread context - When powering on the hotplug slot, in a user thread context The removal of devices and their parent bus may also be done on events or for devices when powering down the slot. To guarantee the existence of the bus and devices until they are no more needed we use kref in zPCI bus and introduce a reference count in the zPCI devices. In this patch the zPCI bus still only accept a device with a devfn 0. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 12:45:43 +03:00
s390/pci: Handling multifunctions We allow multiple functions on a single bus. We suppress the ZPCI_DEVFN definition and replace its occurences with zpci->devfn. We verify the number of device during the registration. There can never be more domains in use than existing devices, so we do not need to verify the count of domain after having verified the count of devices. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-22 16:15:23 +03:00
zpci_free_domain(zbus->domain_nr);
pci_free_resource_list(&zbus->resources);
s390/pci: create zPCI bus The zPCI bus is in charge to handle common zPCI resources for zPCI devices. Creating the zPCI bus, the PCI bus, the zPCI devices and the PCI devices and hotplug slots done in a specific order: - PCI hotplug slot creation needs a PCI bus - PCI bus needs a PCI domain which is reported by the pci_domain_nr() when setting up the host bridge - PCI domain is set from the zPCI with devfn 0 this is necessary to have a reproducible enumeration Therefore we can not create devices or hotplug slots for any PCI device associated with a zPCI device before having discovered the function zero of the bus. The discovery and initialization of devices can be done at several points in the code: - On Events, serialized in a thread context - On initialization, in the kernel init thread context - When powering on the hotplug slot, in a user thread context The removal of devices and their parent bus may also be done on events or for devices when powering down the slot. To guarantee the existence of the bus and devices until they are no more needed we use kref in zPCI bus and introduce a reference count in the zPCI devices. In this patch the zPCI bus still only accept a device with a devfn 0. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 12:45:43 +03:00
s390/pci: Handling multifunctions We allow multiple functions on a single bus. We suppress the ZPCI_DEVFN definition and replace its occurences with zpci->devfn. We verify the number of device during the registration. There can never be more domains in use than existing devices, so we do not need to verify the count of domain after having verified the count of devices. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-22 16:15:23 +03:00
pci_remove_root_bus(zbus->bus);
pci_unlock_rescan_remove();
}
s390/pci: create zPCI bus The zPCI bus is in charge to handle common zPCI resources for zPCI devices. Creating the zPCI bus, the PCI bus, the zPCI devices and the PCI devices and hotplug slots done in a specific order: - PCI hotplug slot creation needs a PCI bus - PCI bus needs a PCI domain which is reported by the pci_domain_nr() when setting up the host bridge - PCI domain is set from the zPCI with devfn 0 this is necessary to have a reproducible enumeration Therefore we can not create devices or hotplug slots for any PCI device associated with a zPCI device before having discovered the function zero of the bus. The discovery and initialization of devices can be done at several points in the code: - On Events, serialized in a thread context - On initialization, in the kernel init thread context - When powering on the hotplug slot, in a user thread context The removal of devices and their parent bus may also be done on events or for devices when powering down the slot. To guarantee the existence of the bus and devices until they are no more needed we use kref in zPCI bus and introduce a reference count in the zPCI devices. In this patch the zPCI bus still only accept a device with a devfn 0. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 12:45:43 +03:00
spin_lock(&zbus_list_lock);
list_del(&zbus->bus_next);
spin_unlock(&zbus_list_lock);
kfree(zbus);
}
static void zpci_bus_put(struct zpci_bus *zbus)
{
kref_put(&zbus->kref, zpci_bus_release);
}
s390/pci: Handling multifunctions We allow multiple functions on a single bus. We suppress the ZPCI_DEVFN definition and replace its occurences with zpci->devfn. We verify the number of device during the registration. There can never be more domains in use than existing devices, so we do not need to verify the count of domain after having verified the count of devices. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-22 16:15:23 +03:00
static struct zpci_bus *zpci_bus_get(int pchid)
{
struct zpci_bus *zbus;
spin_lock(&zbus_list_lock);
list_for_each_entry(zbus, &zbus_list, bus_next) {
if (pchid == zbus->pchid) {
kref_get(&zbus->kref);
goto out_unlock;
}
}
zbus = NULL;
out_unlock:
spin_unlock(&zbus_list_lock);
return zbus;
}
s390/pci: create zPCI bus The zPCI bus is in charge to handle common zPCI resources for zPCI devices. Creating the zPCI bus, the PCI bus, the zPCI devices and the PCI devices and hotplug slots done in a specific order: - PCI hotplug slot creation needs a PCI bus - PCI bus needs a PCI domain which is reported by the pci_domain_nr() when setting up the host bridge - PCI domain is set from the zPCI with devfn 0 this is necessary to have a reproducible enumeration Therefore we can not create devices or hotplug slots for any PCI device associated with a zPCI device before having discovered the function zero of the bus. The discovery and initialization of devices can be done at several points in the code: - On Events, serialized in a thread context - On initialization, in the kernel init thread context - When powering on the hotplug slot, in a user thread context The removal of devices and their parent bus may also be done on events or for devices when powering down the slot. To guarantee the existence of the bus and devices until they are no more needed we use kref in zPCI bus and introduce a reference count in the zPCI devices. In this patch the zPCI bus still only accept a device with a devfn 0. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 12:45:43 +03:00
static struct zpci_bus *zpci_bus_alloc(int pchid)
{
struct zpci_bus *zbus;
zbus = kzalloc(sizeof(*zbus), GFP_KERNEL);
if (!zbus)
return NULL;
zbus->pchid = pchid;
INIT_LIST_HEAD(&zbus->bus_next);
spin_lock(&zbus_list_lock);
list_add_tail(&zbus->bus_next, &zbus_list);
spin_unlock(&zbus_list_lock);
kref_init(&zbus->kref);
INIT_LIST_HEAD(&zbus->resources);
s390/pci: Adding bus resource The current PCI implementation do not provide a bus resource. This leads to a notice being print at boot. Let's do it more nicely and provide the bus resource. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 14:29:37 +03:00
zbus->bus_resource.start = 0;
zbus->bus_resource.end = ZPCI_BUS_NR;
zbus->bus_resource.flags = IORESOURCE_BUS;
pci_add_resource(&zbus->resources, &zbus->bus_resource);
s390/pci: create zPCI bus The zPCI bus is in charge to handle common zPCI resources for zPCI devices. Creating the zPCI bus, the PCI bus, the zPCI devices and the PCI devices and hotplug slots done in a specific order: - PCI hotplug slot creation needs a PCI bus - PCI bus needs a PCI domain which is reported by the pci_domain_nr() when setting up the host bridge - PCI domain is set from the zPCI with devfn 0 this is necessary to have a reproducible enumeration Therefore we can not create devices or hotplug slots for any PCI device associated with a zPCI device before having discovered the function zero of the bus. The discovery and initialization of devices can be done at several points in the code: - On Events, serialized in a thread context - On initialization, in the kernel init thread context - When powering on the hotplug slot, in a user thread context The removal of devices and their parent bus may also be done on events or for devices when powering down the slot. To guarantee the existence of the bus and devices until they are no more needed we use kref in zPCI bus and introduce a reference count in the zPCI devices. In this patch the zPCI bus still only accept a device with a devfn 0. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 12:45:43 +03:00
return zbus;
}
s390/pci: create links between PFs and VFs On s390 PCI Virtual Functions (VFs) are scanned by firmware and are made available to Linux via the hot-plug interface. As such the common code path of doing the scan directly using the parent Physical Function (PF) is not used and fenced off with the no_vf_scan attribute. Even if the partition created the VFs itself e.g. using the sriov_numvfs attribute of a PF, the PF/VF links thus need to be established after the fact. To do this when a VF is plugged we scan through all functions on the same zbus and test whether they are the parent PF in which case we establish the necessary links. With these links established there is now no more need to fence off pci_iov_remove_virtfn() for pdev->no_vf_scan as the common code now works fine. Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Pierre Morel <pmorel@linux.ibm.com> Link: https://lore.kernel.org/r/20200506154139.90609-3-schnelle@linux.ibm.com Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-28 12:54:46 +03:00
#ifdef CONFIG_PCI_IOV
static int zpci_bus_link_virtfn(struct pci_dev *pdev,
struct pci_dev *virtfn, int vfid)
{
int rc;
virtfn->physfn = pci_dev_get(pdev);
rc = pci_iov_sysfs_link(pdev, virtfn, vfid);
if (rc) {
pci_dev_put(pdev);
virtfn->physfn = NULL;
return rc;
}
return 0;
}
static int zpci_bus_setup_virtfn(struct zpci_bus *zbus,
struct pci_dev *virtfn, int vfn)
{
int i, cand_devfn;
struct zpci_dev *zdev;
struct pci_dev *pdev;
int vfid = vfn - 1; /* Linux' vfid's start at 0 vfn at 1*/
int rc = 0;
virtfn->is_virtfn = 1;
virtfn->multifunction = 0;
WARN_ON(vfid < 0);
/* If the parent PF for the given VF is also configured in the
* instance, it must be on the same zbus.
* We can then identify the parent PF by checking what
* devfn the VF would have if it belonged to that PF using the PF's
* stride and offset. Only if this candidate devfn matches the
* actual devfn will we link both functions.
*/
for (i = 0; i < ZPCI_FUNCTIONS_PER_BUS; i++) {
zdev = zbus->function[i];
if (zdev && zdev->is_physfn) {
pdev = pci_get_slot(zbus->bus, zdev->devfn);
cand_devfn = pci_iov_virtfn_devfn(pdev, vfid);
if (cand_devfn == virtfn->devfn) {
rc = zpci_bus_link_virtfn(pdev, virtfn, vfid);
break;
}
}
}
return rc;
}
#else
static inline int zpci_bus_setup_virtfn(struct zpci_bus *zbus,
struct pci_dev *virtfn, int vfn)
{
virtfn->is_virtfn = 1;
virtfn->multifunction = 0;
return 0;
}
#endif
s390/pci: Handling multifunctions We allow multiple functions on a single bus. We suppress the ZPCI_DEVFN definition and replace its occurences with zpci->devfn. We verify the number of device during the registration. There can never be more domains in use than existing devices, so we do not need to verify the count of domain after having verified the count of devices. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-22 16:15:23 +03:00
static int zpci_bus_add_device(struct zpci_bus *zbus, struct zpci_dev *zdev)
s390/pci: create zPCI bus The zPCI bus is in charge to handle common zPCI resources for zPCI devices. Creating the zPCI bus, the PCI bus, the zPCI devices and the PCI devices and hotplug slots done in a specific order: - PCI hotplug slot creation needs a PCI bus - PCI bus needs a PCI domain which is reported by the pci_domain_nr() when setting up the host bridge - PCI domain is set from the zPCI with devfn 0 this is necessary to have a reproducible enumeration Therefore we can not create devices or hotplug slots for any PCI device associated with a zPCI device before having discovered the function zero of the bus. The discovery and initialization of devices can be done at several points in the code: - On Events, serialized in a thread context - On initialization, in the kernel init thread context - When powering on the hotplug slot, in a user thread context The removal of devices and their parent bus may also be done on events or for devices when powering down the slot. To guarantee the existence of the bus and devices until they are no more needed we use kref in zPCI bus and introduce a reference count in the zPCI devices. In this patch the zPCI bus still only accept a device with a devfn 0. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 12:45:43 +03:00
{
s390/pci: Handling multifunctions We allow multiple functions on a single bus. We suppress the ZPCI_DEVFN definition and replace its occurences with zpci->devfn. We verify the number of device during the registration. There can never be more domains in use than existing devices, so we do not need to verify the count of domain after having verified the count of devices. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-22 16:15:23 +03:00
struct pci_bus *bus;
struct resource_entry *window, *n;
struct resource *res;
struct pci_dev *pdev;
s390/pci: create zPCI bus The zPCI bus is in charge to handle common zPCI resources for zPCI devices. Creating the zPCI bus, the PCI bus, the zPCI devices and the PCI devices and hotplug slots done in a specific order: - PCI hotplug slot creation needs a PCI bus - PCI bus needs a PCI domain which is reported by the pci_domain_nr() when setting up the host bridge - PCI domain is set from the zPCI with devfn 0 this is necessary to have a reproducible enumeration Therefore we can not create devices or hotplug slots for any PCI device associated with a zPCI device before having discovered the function zero of the bus. The discovery and initialization of devices can be done at several points in the code: - On Events, serialized in a thread context - On initialization, in the kernel init thread context - When powering on the hotplug slot, in a user thread context The removal of devices and their parent bus may also be done on events or for devices when powering down the slot. To guarantee the existence of the bus and devices until they are no more needed we use kref in zPCI bus and introduce a reference count in the zPCI devices. In this patch the zPCI bus still only accept a device with a devfn 0. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 12:45:43 +03:00
int rc;
s390/pci: Handling multifunctions We allow multiple functions on a single bus. We suppress the ZPCI_DEVFN definition and replace its occurences with zpci->devfn. We verify the number of device during the registration. There can never be more domains in use than existing devices, so we do not need to verify the count of domain after having verified the count of devices. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-22 16:15:23 +03:00
bus = zbus->bus;
if (!bus)
return -EINVAL;
pdev = pci_get_slot(bus, zdev->devfn);
if (pdev) {
/* Device is already known. */
pci_dev_put(pdev);
return 0;
}
rc = zpci_init_slot(zdev);
if (rc)
return rc;
zdev->has_hp_slot = 1;
resource_list_for_each_entry_safe(window, n, &zbus->resources) {
res = window->res;
pci_bus_add_resource(bus, res, 0);
}
pdev = pci_scan_single_device(bus, zdev->devfn);
s390/pci: create links between PFs and VFs On s390 PCI Virtual Functions (VFs) are scanned by firmware and are made available to Linux via the hot-plug interface. As such the common code path of doing the scan directly using the parent Physical Function (PF) is not used and fenced off with the no_vf_scan attribute. Even if the partition created the VFs itself e.g. using the sriov_numvfs attribute of a PF, the PF/VF links thus need to be established after the fact. To do this when a VF is plugged we scan through all functions on the same zbus and test whether they are the parent PF in which case we establish the necessary links. With these links established there is now no more need to fence off pci_iov_remove_virtfn() for pdev->no_vf_scan as the common code now works fine. Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Pierre Morel <pmorel@linux.ibm.com> Link: https://lore.kernel.org/r/20200506154139.90609-3-schnelle@linux.ibm.com Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-28 12:54:46 +03:00
if (pdev) {
if (!zdev->is_physfn) {
rc = zpci_bus_setup_virtfn(zbus, pdev, zdev->vfn);
if (rc)
goto failed_with_pdev;
}
s390/pci: Handling multifunctions We allow multiple functions on a single bus. We suppress the ZPCI_DEVFN definition and replace its occurences with zpci->devfn. We verify the number of device during the registration. There can never be more domains in use than existing devices, so we do not need to verify the count of domain after having verified the count of devices. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-22 16:15:23 +03:00
pci_bus_add_device(pdev);
s390/pci: create links between PFs and VFs On s390 PCI Virtual Functions (VFs) are scanned by firmware and are made available to Linux via the hot-plug interface. As such the common code path of doing the scan directly using the parent Physical Function (PF) is not used and fenced off with the no_vf_scan attribute. Even if the partition created the VFs itself e.g. using the sriov_numvfs attribute of a PF, the PF/VF links thus need to be established after the fact. To do this when a VF is plugged we scan through all functions on the same zbus and test whether they are the parent PF in which case we establish the necessary links. With these links established there is now no more need to fence off pci_iov_remove_virtfn() for pdev->no_vf_scan as the common code now works fine. Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Pierre Morel <pmorel@linux.ibm.com> Link: https://lore.kernel.org/r/20200506154139.90609-3-schnelle@linux.ibm.com Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-28 12:54:46 +03:00
}
s390/pci: Handling multifunctions We allow multiple functions on a single bus. We suppress the ZPCI_DEVFN definition and replace its occurences with zpci->devfn. We verify the number of device during the registration. There can never be more domains in use than existing devices, so we do not need to verify the count of domain after having verified the count of devices. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-22 16:15:23 +03:00
return 0;
s390/pci: create links between PFs and VFs On s390 PCI Virtual Functions (VFs) are scanned by firmware and are made available to Linux via the hot-plug interface. As such the common code path of doing the scan directly using the parent Physical Function (PF) is not used and fenced off with the no_vf_scan attribute. Even if the partition created the VFs itself e.g. using the sriov_numvfs attribute of a PF, the PF/VF links thus need to be established after the fact. To do this when a VF is plugged we scan through all functions on the same zbus and test whether they are the parent PF in which case we establish the necessary links. With these links established there is now no more need to fence off pci_iov_remove_virtfn() for pdev->no_vf_scan as the common code now works fine. Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Pierre Morel <pmorel@linux.ibm.com> Link: https://lore.kernel.org/r/20200506154139.90609-3-schnelle@linux.ibm.com Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-28 12:54:46 +03:00
failed_with_pdev:
pci_stop_and_remove_bus_device(pdev);
pci_dev_put(pdev);
return rc;
s390/pci: Handling multifunctions We allow multiple functions on a single bus. We suppress the ZPCI_DEVFN definition and replace its occurences with zpci->devfn. We verify the number of device during the registration. There can never be more domains in use than existing devices, so we do not need to verify the count of domain after having verified the count of devices. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-22 16:15:23 +03:00
}
static void zpci_bus_add_devices(struct zpci_bus *zbus)
{
int i;
for (i = 1; i < ZPCI_FUNCTIONS_PER_BUS; i++)
if (zbus->function[i])
zpci_bus_add_device(zbus, zbus->function[i]);
pci_lock_rescan_remove();
pci_bus_add_devices(zbus->bus);
pci_unlock_rescan_remove();
}
int zpci_bus_device_register(struct zpci_dev *zdev, struct pci_ops *ops)
{
struct zpci_bus *zbus = NULL;
int rc = -EBADF;
s390/pci: create zPCI bus The zPCI bus is in charge to handle common zPCI resources for zPCI devices. Creating the zPCI bus, the PCI bus, the zPCI devices and the PCI devices and hotplug slots done in a specific order: - PCI hotplug slot creation needs a PCI bus - PCI bus needs a PCI domain which is reported by the pci_domain_nr() when setting up the host bridge - PCI domain is set from the zPCI with devfn 0 this is necessary to have a reproducible enumeration Therefore we can not create devices or hotplug slots for any PCI device associated with a zPCI device before having discovered the function zero of the bus. The discovery and initialization of devices can be done at several points in the code: - On Events, serialized in a thread context - On initialization, in the kernel init thread context - When powering on the hotplug slot, in a user thread context The removal of devices and their parent bus may also be done on events or for devices when powering down the slot. To guarantee the existence of the bus and devices until they are no more needed we use kref in zPCI bus and introduce a reference count in the zPCI devices. In this patch the zPCI bus still only accept a device with a devfn 0. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 12:45:43 +03:00
if (zpci_nb_devices == ZPCI_NR_DEVICES) {
pr_warn("Adding PCI function %08x failed because the configured limit of %d is reached\n",
zdev->fid, ZPCI_NR_DEVICES);
return -ENOSPC;
}
zpci_nb_devices++;
s390/pci: Handling multifunctions We allow multiple functions on a single bus. We suppress the ZPCI_DEVFN definition and replace its occurences with zpci->devfn. We verify the number of device during the registration. There can never be more domains in use than existing devices, so we do not need to verify the count of domain after having verified the count of devices. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-22 16:15:23 +03:00
if (zdev->devfn >= ZPCI_FUNCTIONS_PER_BUS)
s390/pci: create zPCI bus The zPCI bus is in charge to handle common zPCI resources for zPCI devices. Creating the zPCI bus, the PCI bus, the zPCI devices and the PCI devices and hotplug slots done in a specific order: - PCI hotplug slot creation needs a PCI bus - PCI bus needs a PCI domain which is reported by the pci_domain_nr() when setting up the host bridge - PCI domain is set from the zPCI with devfn 0 this is necessary to have a reproducible enumeration Therefore we can not create devices or hotplug slots for any PCI device associated with a zPCI device before having discovered the function zero of the bus. The discovery and initialization of devices can be done at several points in the code: - On Events, serialized in a thread context - On initialization, in the kernel init thread context - When powering on the hotplug slot, in a user thread context The removal of devices and their parent bus may also be done on events or for devices when powering down the slot. To guarantee the existence of the bus and devices until they are no more needed we use kref in zPCI bus and introduce a reference count in the zPCI devices. In this patch the zPCI bus still only accept a device with a devfn 0. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 12:45:43 +03:00
return -EINVAL;
s390/pci: Handling multifunctions We allow multiple functions on a single bus. We suppress the ZPCI_DEVFN definition and replace its occurences with zpci->devfn. We verify the number of device during the registration. There can never be more domains in use than existing devices, so we do not need to verify the count of domain after having verified the count of devices. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-22 16:15:23 +03:00
if (!s390_pci_no_rid && zdev->rid_available)
zbus = zpci_bus_get(zdev->pchid);
if (!zbus) {
zbus = zpci_bus_alloc(zdev->pchid);
if (!zbus)
return -ENOMEM;
}
s390/pci: create zPCI bus The zPCI bus is in charge to handle common zPCI resources for zPCI devices. Creating the zPCI bus, the PCI bus, the zPCI devices and the PCI devices and hotplug slots done in a specific order: - PCI hotplug slot creation needs a PCI bus - PCI bus needs a PCI domain which is reported by the pci_domain_nr() when setting up the host bridge - PCI domain is set from the zPCI with devfn 0 this is necessary to have a reproducible enumeration Therefore we can not create devices or hotplug slots for any PCI device associated with a zPCI device before having discovered the function zero of the bus. The discovery and initialization of devices can be done at several points in the code: - On Events, serialized in a thread context - On initialization, in the kernel init thread context - When powering on the hotplug slot, in a user thread context The removal of devices and their parent bus may also be done on events or for devices when powering down the slot. To guarantee the existence of the bus and devices until they are no more needed we use kref in zPCI bus and introduce a reference count in the zPCI devices. In this patch the zPCI bus still only accept a device with a devfn 0. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 12:45:43 +03:00
zdev->zbus = zbus;
s390/pci: Handling multifunctions We allow multiple functions on a single bus. We suppress the ZPCI_DEVFN definition and replace its occurences with zpci->devfn. We verify the number of device during the registration. There can never be more domains in use than existing devices, so we do not need to verify the count of domain after having verified the count of devices. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-22 16:15:23 +03:00
if (zbus->function[zdev->devfn]) {
pr_err("devfn %04x is already assigned\n", zdev->devfn);
goto error; /* rc already set */
}
zbus->function[zdev->devfn] = zdev;
s390/pci: create zPCI bus The zPCI bus is in charge to handle common zPCI resources for zPCI devices. Creating the zPCI bus, the PCI bus, the zPCI devices and the PCI devices and hotplug slots done in a specific order: - PCI hotplug slot creation needs a PCI bus - PCI bus needs a PCI domain which is reported by the pci_domain_nr() when setting up the host bridge - PCI domain is set from the zPCI with devfn 0 this is necessary to have a reproducible enumeration Therefore we can not create devices or hotplug slots for any PCI device associated with a zPCI device before having discovered the function zero of the bus. The discovery and initialization of devices can be done at several points in the code: - On Events, serialized in a thread context - On initialization, in the kernel init thread context - When powering on the hotplug slot, in a user thread context The removal of devices and their parent bus may also be done on events or for devices when powering down the slot. To guarantee the existence of the bus and devices until they are no more needed we use kref in zPCI bus and introduce a reference count in the zPCI devices. In this patch the zPCI bus still only accept a device with a devfn 0. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 12:45:43 +03:00
zpci_setup_bus_resources(zdev, &zbus->resources);
s390/pci: Handling multifunctions We allow multiple functions on a single bus. We suppress the ZPCI_DEVFN definition and replace its occurences with zpci->devfn. We verify the number of device during the registration. There can never be more domains in use than existing devices, so we do not need to verify the count of domain after having verified the count of devices. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-22 16:15:23 +03:00
if (zbus->bus) {
if (!zbus->multifunction) {
WARN_ONCE(1, "zbus is not multifunction\n");
goto error_bus;
}
if (!zdev->rid_available) {
WARN_ONCE(1, "rid_available not set for multifunction\n");
goto error_bus;
}
rc = zpci_bus_add_device(zbus, zdev);
if (rc)
goto error_bus;
} else if (zdev->devfn == 0) {
if (zbus->multifunction && !zdev->rid_available) {
WARN_ONCE(1, "rid_available not set on function 0 for multifunction\n");
goto error_bus;
}
rc = zpci_bus_scan(zbus, (u16)zdev->uid, ops);
if (rc)
goto error_bus;
zpci_bus_add_devices(zbus);
rc = zpci_init_slot(zdev);
if (rc)
goto error_bus;
zdev->has_hp_slot = 1;
zbus->multifunction = zdev->rid_available;
zbus->max_bus_speed = zdev->max_bus_speed;
} else {
zbus->multifunction = 1;
}
s390/pci: create zPCI bus The zPCI bus is in charge to handle common zPCI resources for zPCI devices. Creating the zPCI bus, the PCI bus, the zPCI devices and the PCI devices and hotplug slots done in a specific order: - PCI hotplug slot creation needs a PCI bus - PCI bus needs a PCI domain which is reported by the pci_domain_nr() when setting up the host bridge - PCI domain is set from the zPCI with devfn 0 this is necessary to have a reproducible enumeration Therefore we can not create devices or hotplug slots for any PCI device associated with a zPCI device before having discovered the function zero of the bus. The discovery and initialization of devices can be done at several points in the code: - On Events, serialized in a thread context - On initialization, in the kernel init thread context - When powering on the hotplug slot, in a user thread context The removal of devices and their parent bus may also be done on events or for devices when powering down the slot. To guarantee the existence of the bus and devices until they are no more needed we use kref in zPCI bus and introduce a reference count in the zPCI devices. In this patch the zPCI bus still only accept a device with a devfn 0. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 12:45:43 +03:00
s390/pci: Handling multifunctions We allow multiple functions on a single bus. We suppress the ZPCI_DEVFN definition and replace its occurences with zpci->devfn. We verify the number of device during the registration. There can never be more domains in use than existing devices, so we do not need to verify the count of domain after having verified the count of devices. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-22 16:15:23 +03:00
return 0;
error_bus:
zpci_nb_devices--;
zbus->function[zdev->devfn] = NULL;
error:
s390/pci: create zPCI bus The zPCI bus is in charge to handle common zPCI resources for zPCI devices. Creating the zPCI bus, the PCI bus, the zPCI devices and the PCI devices and hotplug slots done in a specific order: - PCI hotplug slot creation needs a PCI bus - PCI bus needs a PCI domain which is reported by the pci_domain_nr() when setting up the host bridge - PCI domain is set from the zPCI with devfn 0 this is necessary to have a reproducible enumeration Therefore we can not create devices or hotplug slots for any PCI device associated with a zPCI device before having discovered the function zero of the bus. The discovery and initialization of devices can be done at several points in the code: - On Events, serialized in a thread context - On initialization, in the kernel init thread context - When powering on the hotplug slot, in a user thread context The removal of devices and their parent bus may also be done on events or for devices when powering down the slot. To guarantee the existence of the bus and devices until they are no more needed we use kref in zPCI bus and introduce a reference count in the zPCI devices. In this patch the zPCI bus still only accept a device with a devfn 0. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 12:45:43 +03:00
pr_err("Adding PCI function %08x failed\n", zdev->fid);
zpci_bus_put(zbus);
return rc;
}
void zpci_bus_device_unregister(struct zpci_dev *zdev)
{
struct zpci_bus *zbus = zdev->zbus;
zpci_nb_devices--;
s390/pci: Handling multifunctions We allow multiple functions on a single bus. We suppress the ZPCI_DEVFN definition and replace its occurences with zpci->devfn. We verify the number of device during the registration. There can never be more domains in use than existing devices, so we do not need to verify the count of domain after having verified the count of devices. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-22 16:15:23 +03:00
zbus->function[zdev->devfn] = NULL;
s390/pci: create zPCI bus The zPCI bus is in charge to handle common zPCI resources for zPCI devices. Creating the zPCI bus, the PCI bus, the zPCI devices and the PCI devices and hotplug slots done in a specific order: - PCI hotplug slot creation needs a PCI bus - PCI bus needs a PCI domain which is reported by the pci_domain_nr() when setting up the host bridge - PCI domain is set from the zPCI with devfn 0 this is necessary to have a reproducible enumeration Therefore we can not create devices or hotplug slots for any PCI device associated with a zPCI device before having discovered the function zero of the bus. The discovery and initialization of devices can be done at several points in the code: - On Events, serialized in a thread context - On initialization, in the kernel init thread context - When powering on the hotplug slot, in a user thread context The removal of devices and their parent bus may also be done on events or for devices when powering down the slot. To guarantee the existence of the bus and devices until they are no more needed we use kref in zPCI bus and introduce a reference count in the zPCI devices. In this patch the zPCI bus still only accept a device with a devfn 0. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 12:45:43 +03:00
zpci_bus_put(zbus);
}
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